下颌第一磨牙两壁缺损桩核修复后基牙应力的三维有限元分析  

Three-dimensional finite element analysis on half of the structure defect with post core and all-ceramic crown restoration of mandibular first molar

作　　者：刘涛[1] 耿海霞[1] 荣起国[2] 刘建彰[3] 

机构地区：[1]济宁医学院附属医院口腔科,山东272100 [2]北京大学工学院 [3]北京大学口腔医学院·口腔医院修复科

出　　处：《中华口腔医学杂志》2015年第9期561-564,共4页Chinese Journal of Stomatology

摘　　要：目的 用三维有限元方法分析下颌第一磨牙两壁缺损桩核修复后基牙应力,以期为临床提供参考.方法 用锥形束CT数据建立下颌第一磨牙三维有限元模型,设计6种缺损模式（A：近中壁和舌壁留存;B：远中壁和颊壁留存;C：远中壁和舌壁留存;D：近中壁和颊壁留存;E：近中壁和远中壁留存;F：颊壁和舌壁留存）,分别模拟镍铬合金桩核、金合金桩核、玻璃纤维桩树脂核全瓷冠修复,分别在最大载荷（600 N）、垂直载荷（225 N）、斜向载荷（225 N）和水平载荷（225 N）下,比较缺损模式、修复方式和载荷对基牙von Mises应力分布及最大值的影响.结果 缺损模式对相同修复方式相同载荷下基牙应力分布无明显影响.水平载荷下,镍铬合金桩核修复C缺损模式时基牙yon Mises应力最大值最大,为62.81 MPa.随着载荷侧向力的增加,基牙von Mises应力最大值逐渐增加.结论 下颌第一磨牙两壁缺损时,金合金桩核、玻璃纤维桩树脂核全瓷冠的修复效果优于镍铬合金桩核,牙壁缺损位置对修复效果无明显影响.Objective To make a mechanical analysis on three-dimensional finite element models of the mandibular first molar defect restored with post core and all-ceramic crown,and to provide a guideline for planning restoration for such kind of tooth structure defect.Methods Cone-beam CT based threedimensional finite element models of post and core restored first mandibular molars were established,with 6 different ferrule designs（the ferrule with only 180 axial wall on different locations）.The yon Mises criterion was applied for comparing the maximum von Mises stress value of dentin and stress concentration areas in six models which restored with fiber post or cast NiGr alloy post core or Au alloy post core under the maximum,vertical,inclined and horizontal direct loads.Results The restoration effects in six models were compared,and the maximum yon Mises stress concentration areas were not obviously different.The maximum yon Mises stress value of NiCr alloy post core and crown was 62.81 MPa.Under horizontal load,the maximum von Mises stress value of dentin increased remarkably.Conclusions The location of residual dentin has little influence on the stress distribution,when restored by post core and crown.Au alloy post core and crown or fiber post core and crown are superior to NiCr alloy post core and crown.

关 键 词：有限元分析 磨牙 桩核技术 牙冠(假体) 

分 类 号：R783[医药卫生—口腔医学]